Effects of excessive fluoride on oral mucosal cell DNA synthesis and cell cycle changes in rats

Objective To explore effects of excessive fluoride on oral mucosal cell DNA synthesis and cell cycle changes in rats. Methods Two groups of male SD rats were provided with deionized drinking water containing 0(control group) and fluoride(150 mg/L sodium fluoride) respectively for 4 weeks. Oral mucosal cell DNA damage was measured with single cell gel electrophoresis(or comet assay), DNA relative content(DNA RC ) and cell cycle were detected with flow cytometry. Results Excessive fluoride could reduce the cell number of G 2/M period in cell cycle and decrease DNA relative content significantly in rat oral mucosa. In addition, excessive fluoride could induce rat oral mucosal oxidative stress. The DNA damage rates of excessive fluoride group were 50.20% in oral mucosal cells and were higher than that of the control group significantly. Conclusions It was suggested that excessive fluoride could induce cell cycle changes, decrease DNA relative content and result in oxidative stress and DNA damage in rat oral mucosal cells in vivo.